Programming instructions

15
Temperature Input Modules
These modules are similar to analog input modules, except for the type of input
devices which can be connected. These modules have 4 input channels. With
the FX2N-4AD-TC, thermocouple inputs are used for the detection of
temperature changes, and work off of minute changes in voltage. Type J and
Type K thermocouples are supported. On the FX2N-4AD-PT, the inputs are
special platinum temperature sensors (PT-100 RTD). These sensors can detect
very small temperature changes (.2°C to .3°C .36°F to .54°F). The FX2N-8AD
module’s inputs can also be configured for type K, J, or T thermocouples.
FX3U Left Side Adapter Bus Analog Modules
One of the new features of the FX3U is a new high speed
expansion bus on the left hand side of the PLC. A maximum of 4
analog modules can be used on this left side expansion bus.
There are 4 analog modules available for this left side expansion
bus. These modules include a 4-channel input module, a 4-
channel output module, a 4-channel thermocouple input module,
and a 4 channel RTD input module. These left side expansion
bus modules do not require TO/FROM instructions. The data
from the analog inputs is mapped directly into data registers in
the PLC.
2.7 High Speed Counter & Positioning Modules
There are many options for the FX Series of PLCs to perform high speed pulse
inputs and pulse output motion control. Ordinary counters in the PLC are
dependent on the
scan time in 2 ways: 1) the updating of the input that is used as the counting
input and 2) the updating of the accumulated value of the counter. This may be
too slow for high speed counting applications. The FX Series PLC has built-in
high speed counters, but the maximum counting frequency varies by CPU family,
and this value drops as more high-speed counters are added. Also, inputs are
limited to 24 VDC.
High Speed Counter Module
The FX2N-1HC module provides the high speed counting
ability, up to 50kHz, and has selectable inputs of 5, 12 or 24
VDC. It allows for 2 single phase inputs or one 2-phase input.
It also has two integrated transistor outputs which can be
controlled independently of one another by internal compare
instructions.